So you've made the decision to go with an IP Video Management system. How do you design your network to handle all of the video from the IP cameras? Here's what to think about:
A. Bandwidth available: If you're installing the new camera system on an existing network (not recommended), how much overhead do you have to devote to the new system?
Some common guidelines include:
1. A maximum of 5 Mbps on each network port
2. Not more than 100 Mbps per uplink
3. Not more than 500 Mbps per NVR server port
Remember that to transmit IP video images that are measured in bytes per second across networks that are measured in bits per second, you have to multiply by 8.
B. Power and signal feeds: CAT 5e and CAT6 cabling, already installed in the building, has distinct advantages. Connecting a Power over Ethernet (POE) switch port to an IP camera allows both the signal and the power to be transmitted across the cable. This can result in saving thousands of installation dollars since the additional power cable does not have to be run. Next, determine what the powered device will require from the switch. This is referred to as a POE class, and there are four classes, zero through three, each requiring a different amount of power draw in watts. The design engineer can also figure in uninterrupted power supplies (UPS) back in the data room. When the power is lost, the camera is still recording and video is still available from PCs with UPS backup. It is now easy to figure the power budget by using the following formula:
Number of cameras x power class (in watts) = power budget
C. Traffic Segmentation: There are two different ways to divide or segment traffic on an Ethernet network. One is to physically separate the IP camera network from the company’s production network by running separate network cables and installing new switches. This is by far the most expensive way to segment traffic. The other way is to program Virtual Local Area Networks (VLANs). This method utilizes the existing switch and separates specific ports into their own smaller networks.
Friday, June 26, 2009
Thursday, June 18, 2009
CCD vs CMOS
The image sensor is the camera component which captures light and begins the process of turning it into a digital image. There are two types of security camera sensors: CCD (charge coupled device) and CMOS (complementary metal oxide semiconductor). Which of the two you choose depends on your application.
With a CCD sensor, every individual pixel's charge is transferred through an output node, which is converted into an electrical signal. The signal is then buffered and sent as an analog signal. Because the pixels are devoted to light capture, the image quality is usually pretty high.
With a CMOS sensor, every individual pixel performs its own charge-to-voltage conversion, and the sensor performs amplification and noise-correction. The sensor also includes digitization circuits, which allow the component to output information in a digital format. Because of the complexity of this design, the area devoted to light capture is reduced. And because each pixel must perform its own conversion, uniformity (image quality) is lower.
Both technologies have their place in the marketplace. If your goal is to have good low-light-level surveillance, then a CCD camera is the best. If there is little to no light, CCD sensors used with IR illuminators produce an excellent picture. If indoor lighting is adequate, and megapixel quality is your goal, then CMOS technology may be your best bet.
Make sure you test your camera with the lighting that will actually be present in the field of view. Do not rely on manufacturer’s data sheets for the minimum useable picture. This figure is often subjective, and your customer may not find the results acceptable. CMOS cameras are more prevalent in the IP network world. These cameras are typically equipped with built-in Web Servers, which enable remote viewing of video from other locations, by using IP network protocol.
In conclusion, CCD sensors are the best for outdoor applications, low light scenarios or when a higher quality image is required. CMOS sensor cameras should mostly be considered for indoor applications, though with adequate lighting conditions, they may also work well outdoors.
With a CCD sensor, every individual pixel's charge is transferred through an output node, which is converted into an electrical signal. The signal is then buffered and sent as an analog signal. Because the pixels are devoted to light capture, the image quality is usually pretty high.
With a CMOS sensor, every individual pixel performs its own charge-to-voltage conversion, and the sensor performs amplification and noise-correction. The sensor also includes digitization circuits, which allow the component to output information in a digital format. Because of the complexity of this design, the area devoted to light capture is reduced. And because each pixel must perform its own conversion, uniformity (image quality) is lower.
Both technologies have their place in the marketplace. If your goal is to have good low-light-level surveillance, then a CCD camera is the best. If there is little to no light, CCD sensors used with IR illuminators produce an excellent picture. If indoor lighting is adequate, and megapixel quality is your goal, then CMOS technology may be your best bet.
Make sure you test your camera with the lighting that will actually be present in the field of view. Do not rely on manufacturer’s data sheets for the minimum useable picture. This figure is often subjective, and your customer may not find the results acceptable. CMOS cameras are more prevalent in the IP network world. These cameras are typically equipped with built-in Web Servers, which enable remote viewing of video from other locations, by using IP network protocol.
In conclusion, CCD sensors are the best for outdoor applications, low light scenarios or when a higher quality image is required. CMOS sensor cameras should mostly be considered for indoor applications, though with adequate lighting conditions, they may also work well outdoors.
Monday, June 15, 2009
School Visitor Management Software
Your secretaries might be getting tired of issuing paper badges to visitors and signing them in with pen-and-paper logs. Do they want an easier way to track who is inside the school and make sure everyone is evacuated during an emergency? Are you sure you aren't giving access to suspect individuals?
There's a system to address this. It's called Secure Visitor Management Software (SVMS). SAGE isn't an approved vendor, but the technology is definitely interesting enough to highlight here.
It's very simple to operate. A visitor comes into the lobby and has his or her driver’s license scanned. The SVMS converts the information on the driver’s license to a defined format and prints out a temporary badge allowing access to certain areas of the building, using your existing access control software. The software can even check a national database to ensure visitors aren't on a convicted offender list. (If they are, it sends an email and alerts administrators that he or she is attempting to gain access to the school.) It can even track ongoing custody battles between parents.
Read more about SVMS
There's a system to address this. It's called Secure Visitor Management Software (SVMS). SAGE isn't an approved vendor, but the technology is definitely interesting enough to highlight here.
It's very simple to operate. A visitor comes into the lobby and has his or her driver’s license scanned. The SVMS converts the information on the driver’s license to a defined format and prints out a temporary badge allowing access to certain areas of the building, using your existing access control software. The software can even check a national database to ensure visitors aren't on a convicted offender list. (If they are, it sends an email and alerts administrators that he or she is attempting to gain access to the school.) It can even track ongoing custody battles between parents.
Read more about SVMS
Thursday, June 4, 2009
Designing Access Control
In a traditional wired access control deployment, a door controller is connected back to either a (non-IP) network controller or a building controller. The door controller typically handles two card readers, so it can regulate one or two doors, depending on whether one door is using a card reader for both entrance and exit. It would typically control three devices: a door contact (which tells the system if the door is opened or closed), the door lock and a card reader. Above the door frame would be a powered junction box, which powers each of the devices.
Security systems are now being designed across networks, and are using TCP/IP protocol to communicate to remote devices. Access control is no exception.
In IP-based systems, there is a direct network connection to either the door controller or the card reader, with the network connection providing low-voltage power, typically called Power Over Ethernet (POE). POE powers the door contact, the lock, the card reader and the request to exit (REX) device.
One of the most critical issues in designing access control or any network infrastructure is ensuring the right power source equipment is selected for the job. Many POE network switches do not have full POE capability to every port. When specifying a certain POE switch, make sure it provides the maximum POE wattage of out every port. The current standard is 15.4 watts; however, a new standard of POE plus is being developed, which will provide a maximum wattage of 30 watts.
One excellent example of an IP-based access control system is MAXxess’ netEDGE door controller. The NetEDGE is a high-performance, single-door controller that features a Linux operating system. The Linux OS is embedded in the netEDGE and greatly enhances the reliability and capability of the security management system. In addition, it provides several features to improve performance in any size application.
Because the netEDGE utilizes POE, separate power supplies and multi-door controllers are no longer needed. When utilizing POE for the controllers, readers, lock and REX power, a reduction in installation costs of at least 25% can be realized.
For more information on MAXxess’ netEDGE products, go to http://www.maxxess-systems.com/ or email me at ddamron@sagetechs.com.
Security systems are now being designed across networks, and are using TCP/IP protocol to communicate to remote devices. Access control is no exception.
In IP-based systems, there is a direct network connection to either the door controller or the card reader, with the network connection providing low-voltage power, typically called Power Over Ethernet (POE). POE powers the door contact, the lock, the card reader and the request to exit (REX) device.
One of the most critical issues in designing access control or any network infrastructure is ensuring the right power source equipment is selected for the job. Many POE network switches do not have full POE capability to every port. When specifying a certain POE switch, make sure it provides the maximum POE wattage of out every port. The current standard is 15.4 watts; however, a new standard of POE plus is being developed, which will provide a maximum wattage of 30 watts.
One excellent example of an IP-based access control system is MAXxess’ netEDGE door controller. The NetEDGE is a high-performance, single-door controller that features a Linux operating system. The Linux OS is embedded in the netEDGE and greatly enhances the reliability and capability of the security management system. In addition, it provides several features to improve performance in any size application.
Because the netEDGE utilizes POE, separate power supplies and multi-door controllers are no longer needed. When utilizing POE for the controllers, readers, lock and REX power, a reduction in installation costs of at least 25% can be realized.
For more information on MAXxess’ netEDGE products, go to http://www.maxxess-systems.com/ or email me at ddamron@sagetechs.com.
Thursday, May 21, 2009
Lighting for CCTV surveillance
When capturing video in CCTV surveillance applications, there are three essential elements involved.
Camera:
Make sure the camera has the correct sensitivity for the application.
Sensitivity measures how the camera will respond to a certain level of light to obtain an acceptable picture. Sensitivity is typically measured in lux (1 lux = 1 lumen per square meter), with all camera manufacturers stating the minimum lux level needed to produce acceptable images. Camera manufacturers rarely explain where the minimum LUX level should be measured. Is it the minimum light on the scene, at the front of the lens, or on the camera image chip?
Lens:
The lens must match the camera for the proper amount of light to pass through it.
The lens aperture, or f-stop, determines how much light passes through it to the camera chip. The lower the f-stop, the more light the lens will pass. Many manufacturers will specify a certain f-stop lens with a specific camera. Using the lens specified will guarantee that the proper amount of light will pass through the lens, providing an adequate picture at a certain light level.
Illumination:
Unless we have light, we will have no video images from the camera. There are many sources of light. Some are good and some are not so good for CCTV surveillance.
1. Incandescent lamps - The bulb life is limited and these lights are very inefficient. The maintenance costs on this source of lighting are very high.
2. Fluorescent lamps - These lamps are more efficient than incandescent but still waste up to 60 % of the input energy to heat. These are commonly used indoors and are not used in outdoor applications.
3. High Intensity Discharge (HID) lamps - These are very good for CCTV applications due to their 60 – 80% efficiency and their ability to provide excellent color rendition. Low-pressure sodium is a form of HID lamp but is unsuitable for CCTV applications due to its yellow tinge. The best HID source in use today is metal halide. Metal halide bulbs provide cool white light and have excellent color rendition.
4. LEDs - LEDs are now considered to be the green solution to outdoor lighting. They are extremely efficient, and their reliability cannot be matched.
Camera:
Make sure the camera has the correct sensitivity for the application.
Sensitivity measures how the camera will respond to a certain level of light to obtain an acceptable picture. Sensitivity is typically measured in lux (1 lux = 1 lumen per square meter), with all camera manufacturers stating the minimum lux level needed to produce acceptable images. Camera manufacturers rarely explain where the minimum LUX level should be measured. Is it the minimum light on the scene, at the front of the lens, or on the camera image chip?
Lens:
The lens must match the camera for the proper amount of light to pass through it.
The lens aperture, or f-stop, determines how much light passes through it to the camera chip. The lower the f-stop, the more light the lens will pass. Many manufacturers will specify a certain f-stop lens with a specific camera. Using the lens specified will guarantee that the proper amount of light will pass through the lens, providing an adequate picture at a certain light level.
Illumination:
Unless we have light, we will have no video images from the camera. There are many sources of light. Some are good and some are not so good for CCTV surveillance.
1. Incandescent lamps - The bulb life is limited and these lights are very inefficient. The maintenance costs on this source of lighting are very high.
2. Fluorescent lamps - These lamps are more efficient than incandescent but still waste up to 60 % of the input energy to heat. These are commonly used indoors and are not used in outdoor applications.
3. High Intensity Discharge (HID) lamps - These are very good for CCTV applications due to their 60 – 80% efficiency and their ability to provide excellent color rendition. Low-pressure sodium is a form of HID lamp but is unsuitable for CCTV applications due to its yellow tinge. The best HID source in use today is metal halide. Metal halide bulbs provide cool white light and have excellent color rendition.
4. LEDs - LEDs are now considered to be the green solution to outdoor lighting. They are extremely efficient, and their reliability cannot be matched.
Monday, May 11, 2009
Is H.264 Compression Becoming the Standard for Security Manufacturers?
Product managers and engineers constantly look for technologies that will shape the future security industry. We all agree that we need better image quality, faster transmission speeds, quicker emergency response times and improved storage efficiency. Most CCTV camera and DVR manufacturers now look to H.264 for the solution. Many of their data sheets now mention compression of H.264 as well as MPEG-4 and JPEG.
H.264 is simply an improved version of MPEG-4 with more efficient video compression technology. H.264 requires roughly half the storage space as MPEG-4. So what benefit does this provide for the end user? Since it is more efficient than MPEG-4, H.264 gives better image quality per bit of data. The system needs less bandwidth to transmit the video from IP camera to the network video recorder. That means it can be used on existing networks, cutting upgrade expenses. The end user can store more information on less hard drive capacity and lower installation costs.
As with any new technology, there may be some drawbacks. H.264 does require more processing power to decode the video. Manufacturers may utilize multiple processors to improve performance. Consider the cost versus the benefit.
When should you upgrade to H.264 technology? If a current system is only handling 6-7 cameras at 4-5 frames per second, 24 hours per day, H.264 may not be needed. If the existing system is not taking up much of its available storage space and the installed cameras are not streaming large amounts of data, H.264 is unnecessary. However, in systems with IP cameras, megapixel cameras or cameras requiring high framerates (like banking and casino applications), H.264 would definitely be a viable solution.
H.264 is simply an improved version of MPEG-4 with more efficient video compression technology. H.264 requires roughly half the storage space as MPEG-4. So what benefit does this provide for the end user? Since it is more efficient than MPEG-4, H.264 gives better image quality per bit of data. The system needs less bandwidth to transmit the video from IP camera to the network video recorder. That means it can be used on existing networks, cutting upgrade expenses. The end user can store more information on less hard drive capacity and lower installation costs.
As with any new technology, there may be some drawbacks. H.264 does require more processing power to decode the video. Manufacturers may utilize multiple processors to improve performance. Consider the cost versus the benefit.
When should you upgrade to H.264 technology? If a current system is only handling 6-7 cameras at 4-5 frames per second, 24 hours per day, H.264 may not be needed. If the existing system is not taking up much of its available storage space and the installed cameras are not streaming large amounts of data, H.264 is unnecessary. However, in systems with IP cameras, megapixel cameras or cameras requiring high framerates (like banking and casino applications), H.264 would definitely be a viable solution.
Friday, May 8, 2009
Sample security maintenance schedules
Daily maintenance:
1. Confirm there are no errors displaying on any of the DVRs.
2. Verify proper PTZ control on all movable cameras.
3. Create an operational log and make entries daily of any issues/problems which need to be addressed by on site personnel or the installing company.
Weekly maintenance:
1. Check all cameras for normal video.
2. Verify video is being recorded by performing a search for a specific period of time. Archive video from the DVR to a CD or DVD using the management software.
3. Check the satisfactory transmission of images to remote center (where applicable).
Monthly maintenance:
1. Clean all system monitor screens with appropriate glass cleaner.
2. Wipe down all head-end equipment with a dry, lint-free cloth to keep the equipment clean.
3. Ensure that the camera has a proper field of view and that fixed cameras have not been repositioned.
4. Verify the required retention rate by checking the oldest video saved on the DVRs.
Semiannual Maintenance Schedule:
1. Visually inspect all major CCTV components (including cabling and connections, where accessible) for signs of deterioration or damage.
2. Check and clean cameras, lenses and housings as necessary.
3. Clean (vacuum and dust) internal workings of DVR.
4. Check hard drives on all DVRs.
5. Perform software upgrades when available.
6. Test UPS.
1. Confirm there are no errors displaying on any of the DVRs.
2. Verify proper PTZ control on all movable cameras.
3. Create an operational log and make entries daily of any issues/problems which need to be addressed by on site personnel or the installing company.
Weekly maintenance:
1. Check all cameras for normal video.
2. Verify video is being recorded by performing a search for a specific period of time. Archive video from the DVR to a CD or DVD using the management software.
3. Check the satisfactory transmission of images to remote center (where applicable).
Monthly maintenance:
1. Clean all system monitor screens with appropriate glass cleaner.
2. Wipe down all head-end equipment with a dry, lint-free cloth to keep the equipment clean.
3. Ensure that the camera has a proper field of view and that fixed cameras have not been repositioned.
4. Verify the required retention rate by checking the oldest video saved on the DVRs.
Semiannual Maintenance Schedule:
1. Visually inspect all major CCTV components (including cabling and connections, where accessible) for signs of deterioration or damage.
2. Check and clean cameras, lenses and housings as necessary.
3. Clean (vacuum and dust) internal workings of DVR.
4. Check hard drives on all DVRs.
5. Perform software upgrades when available.
6. Test UPS.
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